There are number of different applications available for data recovery, restoring deleted files. But many of them are costly and other freewares come with plenty of advertisements, pop-ups, ad-ware, spyware etc. Most people don't wish to spend on such applications or download false freewares.

I personally use and recommend Free Undelete from OfficeRecovery.com. There is no charge, direct or hidden, to download and use a fully functional copy of the program. The program does not install any spyware or adware along with it. It does not populate user's desktop with pop-up ads or forcefully subscribe user to mailing lists.